Persistent p53 mutations in single cells from normal human skin
Persistent p53 mutations in single cells from normal human skin
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DOI：
10.1016/s0002-9440(10)62511-4
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发表时间：
2001-10-01
影响因子：
6
通讯作者：
Ponten, F
中科院分区：
文献类型：
--
作者：
Ling, G;Persson, A;Ponten, F
P53基因突变的角质形成细胞的表皮克隆在慢性日晒皮肤中大量存在，可能在皮肤癌的早期发展中起重要作用。先进的激光捕获显微切割技术能够对组织切片中的目标细胞进行基因分析，而不会受到邻近细胞的污染。在这项研究中，研究了来自正常、长期暴露在阳光下的皮肤的单个细胞中的p53基因突变。活体组织取自每天接受夏日阳光照射的皮肤和用蓝色牛仔布料完全防晒的皮肤。使用激光捕获显微切割技术，从4例活检组织中提取172例单细胞样本，并采用单细胞聚合酶链式反应和DNA直接测序进行分析。在99个角质形成细胞中的26个中发现了14个不同的突变，从中可以扩增出p53基因。突变表现出典型的紫外线特征，在分散的角质形成细胞和一小群P53免疫反应的角质形成细胞中都检测到了突变。这个微小的表皮p53克隆的直径为10-15个基底细胞。在p53克隆的所有表皮层中都发现了两个错义突变。目前的数据显示，P53突变在正常皮肤中很常见，尽管紫外线完全保护了两个月，但带有突变P53基因的角质形成细胞克隆仍然占上风。
Epidermal clones of p53-mutated keratinocytes are abundant in chronically sun-exposed skin and may play an important role in early development of skin cancer. Advanced laser capture microdissection enables genetic analysis of targeted cells from tissue sections without contamination from neighboring cells. In this study P53 gene mutations were characterized in single cells from normal, chronically sun-exposed skin. Biopsies were obtained from skin subjected to daily summer sun and skin totally protected from the sun by blue denim fabric. Using laser capture microdissection, 172 single-cell samples were retrieved from four biopsies and analyzed using single-cell polymerase chain reaction and direct DNA sequencing. A total of 14 different mutations were identified in 26 of 99 keratinocytes from which the P53 gene could be amplified. Mutations displayed a typical UV signature and were detected in both scattered keratinocytes and in a small cluster of p53-immunoreactive keratinocytes. This minute epidermal P53 clone had a diameter of 10 to 15 basal cells. Two missense mutations were found in all layers of epidermis within the P53 clone. The presented data show that p53 mutations are common in normal skin and that a clone of keratinocytes with a mutated p53 gene prevailed despite 2 months of total protection from ultraviolet light.